There are a number of various types of temperature-sensing devices in the marketplace which are, for their particular use, reasonably accurate and acceptable. However, it has been found that existing thermometers, or other temperature sensing devices, are inadequate for measuring temperatures along the surface in a sufficiently short period of time before the surface cools in order to otherwise display or sense accurately a profile of the entire surface temperature.
An example of problems with certain temperature measuring instruments is with those used in conjunction with race cars. During the course of a race, it is often necessary to measure the temperature of the tires to insure that the right tires are being used and that they are utilized at the correct pressure among other possible parameters. These parameters are used to enhance the operation of the individual car during the course of a race and to avoid damage to the tire.
When the race car pulls off the track, the tires cool rapidly. Those temperature sensing devices utilizing single probe members and recording only a single temperature, cannot be actuated in a manner which will permit determination of the profile across the entire tire. As a result, by the time the operator takes individual temperature readings at various portions of the tire, the tire has sufficiently cooled so that an accurate tire profile cannot be acheived. Rather, what will be shown is a change in temperature due to the cooling mechanism rather than other parameters of tire pressure, size, weight, speed, etc.
The invention herein has overcome many of the deficiencies in measuring temperatures of surfaces which can change rapidly where the temperature surface profile is desired. In the invention described herein, an electronic apparatus is utilized with a temperature sensing means to measure the temperature across the entire width of a desired surface and specifically that of a tire. For this purpose, the temperature sensing means is connected to a sensor interface for converting the analog temperature sensed into a digital output that can be used by the remainder of the apparatus.
A microprocessor, having read only memory for storage of a program operates a system in conjunction with memory or data storage means and a display to retrieve data from the memory and display it in either graphical or digital form for readout by the operator. A keyboard having the desired command keys is integrated with the other elements of the system discussed above to command the system to make the measurements, recall previous measurements and display specific measurements and profiles. In addition, various other keys can be incorporated to perform certain arithmetical and other functions to compare current and previous measurement profiles. Since it is often desirable to compare a current profile with that of one taken some time before, the apparatus includes a means for storing previous profiles and recalling them for comparison with more recent temperature readings. For this purpose, a number of different types of sensors can be used such as thermistors, semiconductor temperature sensors, resistance temperature detectors, thermocouples, or non-contact infrared temperature sensors. The sensor utilized must be one which has a rise time to the maximum reading of less than 2 seconds and has a temperature range preferably between 0.degree. C. to 150.degree. C.
Tha above has been a brief description of the deficiencies of the prior art and the advantages of the invention described herein. Other advantages can be perceived from the detailed discussion of the preferred embodiment which follow.